Gear system with flywheels



Sept 14, 1937. H. EOTTINGER 9 GEAR SYSTEM WITH FLYWHEELS- Filed Oct. 17, 1954. 3 Sheets-Sheet 2 Sept. 14, 1937. H. FOTTINGER 2,G93,M2

GEAR SYSTEM WITH FLYWHEELS Filed oct. 1'7, 1934 5 Sh'ee'cs-Sheet Azo' Patented Sept. 14, 1937 UNITED STATES ATENT OFFICE GEAR SYSTEM WITH FLYWHEELS Hermann Fiittinger, Berlln-Wilmersdori', Germany Application October 17,1934, Serial 1m; 748,700

In Germany October 19,- 1933 16 Claims. (Cl. 74-1895) The invention relates to a gear'system for nite maximum torque M=Ml=Mll which with starting, rapidly accelerating and keeping in increasing n: drops at firstslowly and then inmovement any inert masses, such as flywheels, creases more quickly and eventually disappears tube mills, pumps with long pressure piping or when synchronism (m=nl) is arrived at. a v

5 entire machines, which gear comprises small In the same measure as the torques are'also 5 motors, hydraulic or mechanical gears per se changed the horse-power is tobe spent when the known and small auxiliary flywheels rotating primary speed is kept constant. v at high speed. I have already suggested devices The efliciency of transmission 1; (=ratio of for accelerating railroad trains driven by lowthe horse-powers Nz:N1) then increases linearly speed combustion engines which are provided from nil to 100 per cent. 10

' with flywheels storing the starting power and For many purposes, e. g. the drive of heavy adapted to be driven and charged or the enmachines or the like by combustion the following ergy stored by the main shaft through an ar-' drawbacks will result from this system: rangement changing over to a higher speed. In '(1) In the majority of cases the engines will that instance it was intended to transmit the run with throttled speed; theretore the auxiliary 15 power to the rotating masses by one or more flywheels connected thereto by means of slip disconnectable electric or hydraulic asynchronous couplings will practically almost never be accelcouplings. Even by this prior invention it was erated to their admisslblemaximum speed, viz. possible to have for use, in starting and for a fully charged'fl'that is charging oi the flywheel definite time, the multiple of the continuous outc with energy. and utilized. p

put of the engine otherwise available. The ob- (2) Practically the slip couplings will be so ject of this invention is to extend this type of dimensioned that at high secondary speeds 112 power multiplication by storing to a substantially and continuous output they result in a slip as enlarged field and to improve it economically small as possible (2 to 5%). When thefiywheel while at the same time there are obviated the is-beingstarted the amount of slip is however as 25 inconveniences inherent in the system so far high as 100%.

known and chiefly consisting in the exclusive The torque characteristics Fig. however, use of asynchronous couplings. show that at the start the engine torques should Referring to the drawings: be 10 to 20 times higher than those oi continu- Figure 1 is a diagram showingthe moment ous operation; As the majority of prime movers, 30 characteristic of a drive with a Ftittinger couparticularly combustion engines are notable to pling comply with this requirement, the engine speed Fig. 2 is a similar view utilizing a Ftittinger cannot be kept constant as presumed in Fig. 1 transformer, and but will drop to A or V 85 Figs. 3 to 6 are diagrammatic elevational views, In this instance alsothe output of the engine 85 partly in section of diflerent modified construcwill be'reduced to; a corresponding fraction, viz. tional mechanisms according to this invention. also the engine can be'utilized to a smallfraction Hydraulic asynchronous couplings comprise a only when the flywheel is being charged. 7 primary or pump wheel I and a secondary or (3) The said tenfold or twentyfold increase of 40 turbine wheel II without stationary parts of rethe torque howeverv also takes place when the 40 action, particularly stationary guide wheels. flywheel is discharged 0! its energy and the mass Both the primary and secondary torques M1 and of the machine or the like is started, .but for M: are therefore of exactly the same magnitude, many purposes this amount is excessive, which neither an increase of the torque (conversion of fact involves th 1 1; th t t t m m power) nor an increase of the secondary speed m her break; th drivi wh l dth fr ti 46 beyond the Primary Speed m being thus Possible clutches, it any, slide and that inadmissible slip is Practically there must even exist a certain produced m any asynchronous 1mm existing amount of S111) unless the latter are extremely large,,which is l nlm heavy and expensive. 50 m ,1 to 5% According to this-invention all these incon- When the primary speednl is kept constant by venlences are obviated in that the charging meansof a sufliciently powerful prime mover and alid/01 discharging of the auxiliary rotating the secondary speed n2 is modified by thev applimasses can be accomplished by means oi.- separate cation of various resistances, according to Fig. 1 y au ic transmi s 8 84's with 81 81 there is transmitted in the start (1l2=0) a defl- 8111118 fl. 8 6. q e C e e 0! Short converters which can be used in addition to or instead of the slip couplings having no guide wheels.

Fig. 2 shows the absolutely different properties of these converters, ,again on the supposition that the engine speed: 111 is kept constant, in dependence on thesecondary speed m variable in accordance with the resistance opposed. In this instance the secondary torque'Mz may exceed five to eight times the engine torque M1 at starting (m=0),.v according to the normal ratio of transmission, computed for the normal run. When n: increases, M2 drops along a curve which is concave at the top. With this arrangement 11.: can appreciably exceed the speed correspond-:

lized.

The excessive increase of the torque in the discharge will not take placeany more. The curve of the e'fllciency '17 will vary in accordance with a flat curve having an apex and an increased mean value.

Of paramount importance is the substantial increase of the ratio of speeds as effected by the converter. According to the invention. this in.- crease further permits the imparting to the hywheel, with the aid of the ratio"of the toothed gearing, circumferential speeds as high as 400 to 500 meters per second so that, as compared with 'prior inventions, the weight of the flywheel can be reduced to one tenth, the small flywheels being forged of very high-grade steel so as to be adapted to the stress developed on account of the increased circumferential speed.

The enormously reduced flywheel weights also result in decreased losses. in bearing friction and wind resistance.

According to the invention the converter can also be combined with and alternatingly used instead of the hydraulic slip coupling. As the efflciency of a converter is lower than that of a coupling used with small slip, it is possible to replace the action of the converter by that of a coupling in the range. of speeds in which the primary and secondary speeds do not sensibly differ, viz. in the range of the speed of synchronism, the said coupling being cut out directly before the'speed of synchronism is arrived at, and replaced again by the converter in order that'a higher secondary speed'can be attained. This system of working aifords the highest eiflciency figures.

Also for discharging the auxiliary flywheels thereis preferably arranged between the rotating mass and the toothed gearing a separate converter in which the primary and the' secondary wheels are disposed inversely as compared with the converter intended for charging energy. For instance, while discharging, there is used at first the said converter, subsequently the coupling equally suitable for charging and discharging, and eventually the converter again.

Figs. 3 to 6 diagrammatically show several embodiments of the invention by way of example, Fig. 3 illustrates the combination with the slip coupling K suitable for charging and discharging the flywheels l3 of the energy and I3, and a converter W intended for charging.

The driving engine I, e. g. a combustion enzinc, is connected with the pinions 4 and l through the main shaft 2 and the large gear wheel 3.

In order that the gyroscopic eifect, produced by the increased speed of the flywheels, is obviated, there is interposed an intermediate gear wheel 4 between the gear wheel 3 and the pinion ,4' so that the two flywheels l3 and I3 rotate in different directions and with contrary gyro scopic effects. The pinions 4 and A are secured to hollow shafts 5 and 5 which are in turn each rigidly connected with a wheel of the couplings K and K respectively having no guide wheel and the pump wheels I and 1' respectively of converters W and W respectively provided with astationary guide wheel ll. The corresponding secondary wheels l0 and II respectively of the coupling K and the converter W are keyed on a shaft 9 revoluble within the hollow shaft 5 and carrying the flywheel I3 at its other end. Between the large gear wheel 3 and the driven shaft H5 is interposed a disconne'ctable coupling ll which may be a hydraulic or a mechanical coupling or a combination of hydraulic and mechanical couplings or of any other .type, e. g., a freewheel susceptible of being disconnected if neces- When the flywheels l3 and I3 are to be charged with energy in the machine which has not yet started, the coupling I1 is disconnected and the converter.W thrown in. On account of the functionsalready stated of the converter the speed and the output of the driving engine I can be adjusted to their full amount and the flywheels charged within a very short time and with highefliciency. Charging energy may also be accomplished by braking the vehicle in which case the braking energy of the mass of the vehicle is stored for the acceleration phase of the flywheel. In the latter instance the coupling I1 is thrown in and the engine throttled but temporarily.

existing between the primary and secondary speeds amounts to, e. g., 20 .to 15% only. This being the case, the couplinggK assumes the transmission until at 2 to 3% slip the converter W is thrown in again and caused to bring the flywheels up to thesupersynchronous speed.

Fig. 4 shows an embodiment in which between the pinion 4 and the flywheels I3 there is inserted an additional converter W1 the primary wheel I: of which is connected with the flywheel shaft and the secondary wheel 8 with the hollow shaft 5. The: said converter W1, when combined with the coupling K, permits any regulation desired of the torque when the flywheel is being discharged of its energy. I

In either embodiment the flywheels may also be temporarily accelerated or kept in motion by separate driving engines coupled with the shaft 9, such as electric motors, steam, exhaust-gas or compressed-air turbines. Fig. 4 of thedrawings shows a modification for such an auxiliary drive.

The two flywheels l3 and I3 are driven by the small turbines 2i and 2| which are of a type which may be driven by exhaust gases or steam.

or also by fluids. The same may be fed and provided with the driving fluid from the main engine or any other engine or indirectly from a hydraulic transmission gear connected thereto.

To the single transmission gear 3, I intended for charging and discharging energy into and from the flywheels there may also be substituted, according to Fig. 5, two gears, 3, 4, and 3a, 4a one of which is used for charging energy andthe other for discharging the stored energy. In this case the flywheels'are e. g. disposed between the pinions and capable of being disconnected on either side by a converter W and/or a coupling K from the particular gearing. This arrangement affords the advantage that the coupling l'l keyed on the main shaft must be dimensioned for the maximum torque of the engine I only while in the case of the prior embodiments it had to be proportioned for transmitting the enormous additional torque of the flywheels.

As the very high speed of the flywheels would result in very small dimensions of the hydraulic gears, practically almost unfeasible, it is also possible to make the mechanical gears with two stages and to dispose the hydraulic couplings and/or converters on the intermediate shaft as or the engine is'running with a reduced output,

which energy is utilized as an additional multiple engine output when it is a question of accelerating the vehicle again. The latter then requires a comparatively weak driving engine since the largest portion of the energy is stored. The same arrangement can also be used for the drive of working machines, such as mills, pumps, lifting and conveying machines, converters and machines which are subject to intermittent loads in railroad service or rolling mills.

A particular advantage is then afforded by the fact that e. g. in the case of electric drive, both the distributing network and the power station are largely relieved from high peak outputs, especially in railroad or tramway service, so that the size of the machines to be held at disposal and thus the capital cost can be correspondingly reduced.

On account of the increase of speed made possible by the converter described the energy to be spent for accelerating an automobile weighing 1200 kg., from nil to 72 km. per hour can be developed by an auxiliary flywheel of 2 kg. only, on the assumption of an ideal transmission and by an 8 kg. flywheel when the efficiency amounts to 25%.

I claim:

1. A gear system, comprising a main driving shaft, a driven shaft, a coupling interposed be- .tween said driving and driven shafts and adapted to connect or disconnect same, a second pair of shafts, a gearing connecting the one shaft of said second pair with the driving shaft, a flywheel adapted to be charged by said driving shaft and mounted on the second shaft of said second pair, and a converter having a stationary wheel and rotatable wheels which latter are connected with the 'two shafts of the second pair respectively. V

2. A gear system according to claim 1, in which a hydraulic coupling is provided .the two parts of which are also connected with the two shafts of the second pair respectively, so that said flywheel may be charged and discharged by means of said converter and said coupling alternatively.

3. A gear system, comprising a main driving shaft, a driven shaft, a couplinginterposed betweensaid driving and driven shafts and adapted to connect or disconnect the'shafts, aplurality of further pairs of shafts, a gearing conpairs with the driving shaft, a plurality of flywheels adapted to be charged and discharged by said driving shaft and each mounted on one of the second shafts. of said further pairs, and a necting theone shaftof each of said further plurality of converters each having a stationary wheel and rotatable wheels the latter of which are connected with the two shafts of one of the said further pairs of shafts respectively.

4. A' gear system according to claim 3, inwhich a plurality of hydraulic couplings are provided, the two parts of each of said couplings also being connected with the two shafts of one of the said further pairs. of shafts respectively so that the flywheels .may be charged and discharged by means of. said converters and said couplings alternatively. v

5. A gear system, comprising a main driving shaft,;a driven shaft, a couplinginterposed between said driving and driven shafts and adapted to connect or disconnect the shafts,.a second .7

pair of shafts, a gearing connecting one shaft of said second pair with the driving shaft, a,

flywheel adapted to be charged by said driving shaft and mounted on the second shaft of said second pair, and two converters each having a stationary wheel and rotatable wheels the latter of which are connected with the two shafts of the second pair respectively. i

6. A gear system accordingto claim 5, in which a hydraulic coupling is provided the two parts of,

which are also connected with the two shafts of the second pair respectively so that said flywheel may be charged and discharged by means of said converters and said coupling alternatively. i 7. A gear system comprising a main driving shaft, a driven shaft, a coupling interposed be-.

tween said driving and driven shafts and adapted to connect or disconnect the shafts; a sec-' ond pair of shafts, two pinions arranged on one shaft of said second pair and on the driving shaft respectively and connecting these shafts,

a flywheel adapted'to be charged by said driving shaft and mounted on the second shaft of said second pair, and a converter interposed between the pinions and the flywheel in the.direction of the flow of power and having a stationary wheel and rotatable wheels the latter .of which are connected with the two shafts of the second pair respectively. g

8; A gear system according to claim 7, in which a hydraulic coupling is provided the two parts of which are also interposed between the pinions and the flywheel in the direction of the flow of power and connected with the two shafts of the second pair respectively so that said flywheel maybecharged and discharged by means of said converter and said coupling alternatively.

9. A gear system, comprising a driving main shaft, a driven shaft, 8. coupling interposed between said driving and driven shafts and adapted to connect or disconnect the shafts, a hollow shaft, a gearing connecting said hollow shaft with the driving shaft, a further shaft revolvable with- .in said hollow shaft, a flywheel adapted to be charged by the said driving shaft and mounted on said further shaft, and aconverter having a stationary wheel and rotatable wheels the latter of which are connected with the said hollow shaft and said further shaft respectively.

10. A gear system, comprising a main' driving shaft, a driven shaft, a coupling interposed between said driving and driven shafts and adapted to connect or disconnect the shafts, a hollow shaft, a gearing connecting said hollow shaft 2o coupling the rotatable wheels of which are connected with the said hollow shaft and said further shaft respectively.

11. A gear. system, comprising a main driving shaft, a driven shaft, a coupling interposed between said driving and driven shafts and adapted to connect or disconnect the shafts, a second pair of shafts, a gearing connecting the one shaft of said second pair with the driving shaft, a flywheel adapted to be charged by said driving shaft and mounted on the second shaft of the said seciii! the flywheel, and a second converter having a stationary wheel and rotatable wheels the latter of which are connected with: the two shafts of the second pair respectively and serving for discharging the flywheel.

12. A gear system, comprising a main driving shaft, a driven shaft, a coupling interposed between said driving and driven shafts and adapted to connect or disconnect the shafts, two further shafts, two gearings the one: connecting the driving shaft and the other connecting the driven shaft with the two further shafts, a flywheel on each of said further shafts, and a pair of hydraulic couplings on each of said further shafts,

one coupling of said pairs being arranged be- 13. A gear system according to claim 12, in which a converter having a stationary wheel is provided in place of one coupling of each pair.

14. A gear system, comprising a main driving shaft, a driven shaft, a coupling interposed between said driving and-driven shafts and adapted to connect or disconnect the shafts, a second pair of shafts, a gearing connecting the one shaft of said second pair with the driving shaft, a converter having a stationary wheel and rotatable wheels the latter of which are connected with the two shafts of the second pair respectively, a further shaft, a second gearing connecting the second shaft of said second pair with said further shaft, and a flywheel adapted to be charged by said driving shaft and mounted on the further shaft.

15. A gear system, comprising a main driving shaft, a driven shaft, a coupling interposed between saiddriving and driven shafts and adapted to connect or disconnect the shafts, a plurality of further pairs of shafts, a gearing connecting the one shaft of. each of said further pairs of shafts with the driving shaft, a plurality of flywheels adapted to be charged and discharged by said driving shaft and each mounted on one of the second shafts of said further pairs, and a plurality of converters each having a stationary wheel, the rotatable wheels of each converter being connected with the two shafts of one of the said further pairs of shafts respectively, and the gearing being so devised that one half of said flywheel rotates in the one direction and theother half in the other direction.

16. A gear system, comprising a main driving shaft, a driven shaft, a coupling interposed between said driving and driven shafts and adapted to connect or disconnect the shafts, a second pair of shafts, a gearing connecting the one shaft of said second pair with the driving shaft, a flywheel adapted to be charged by said driving shaft and mounted on the second shaft of said second pair, a converter having a stationary wheel and rotatable wheels the latter of which are connected with the two shaftslof the second pair respectively, and means provided on the second shaft of said second pair of shafts and adapted to drive said second shaft directly thereby-charging the flywheel.

HERMANN FU'I'I'INGER. 

